Quote Originally Posted by Antaresia View Post
The guys also upgraded my parts form Tigra (what I ordered) to 105 at no extra cost.
I hesitate to mention this, but your cranks are neither current model Tiagra nor 105. First off, they are using an internal cartridge bottom bracket. (This is actually not necessarily bad.) Second, the backs of the arms are concave - which means they aren't made with "hollow" technology.

They look kind of like Shimano FC-R453 cranks.